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At least 595 records · Page 33

Humble planar defects in SiGe nanopillars

We report a {001} planar defect found in SiGe nanopillars. The defect structure, determined by atomic-resolution electron microscopy, matches the Humble defect model proposed for diamond. We also investigate several possible variants of the Humble structure using first-principles calculations and find that the one lowest in energy is in agreement with the scanning transmission electron microscope images. The pillar composition has been analyzed with electron energy loss spectroscopy, which hints at how the defect is formed. Our results show that the structure and formation process of defects in nanostructured group IV semiconductors can be different from their bulk counterparts.

36 MATERIALS SCIENCE↗

TH-D-16A-01: Medical Physics Workshop: Editorial Vision and Guidance On Writing and Reviewing Papers

On January 1, 2014, editorial leadership of Medical Physics passed from esteemed long-time Editor Bill Hendee to a collective editorial group composed of the three presenters listed above. In this presentation, we would like to outline our vision for the future of Medical Physics and review recent work-in-progress initiatives to implement this vision. Finally, we will close with guidance to authors on how to write a good Medical Physics paper. Vision for Medical Physics and current initiatives: Jeff Williamson, Editor-in-Chief We cannot improve on Dr. Hendee's succinct vision statement “to continue the Journal's tradition of publishing the very best science that propels our discipline forward and improves our contribution to patient care.” More concretely, the Journal should be s the preeminent forum for electronic exchange of cutting edge medical physics science. We seek to identify the best contributions in (a) high impact clinical physics innovations; (b) clinical translation and validation of basic science innovations; or (c) cutting edge basic science developments with potential for patient care improvements. Among the challenges and opportunities we face are: are electronic-only and open access publishing; trends towards more interactive, social-media based scientific communities; and diversification of the medical physics research, authorship, and readership domains, including clinical applications quite foreign to core ABR clinical competencies. To address these issues over the next 3 years, we have reduced the size of our Editorial Board and focused its efforts on improving the Journal's impact through 4 working groups (WGs): WG-1: Review process quality and selectivity Creation of 120 member Board of Associate Editors to improve review uniformity by placing Ms. management in fewer hands New reviewer guidelines and templates Answer: “what is the scope of medical physics research?” Recursive taxonomy for tagging review expertise and article contents WG-2 Improving reader experience Redesigning http://MedPhys.org to host interactive features and gateway to electronic issue archive Experimentation with interactive features beginning with “Point/Counterpoint” Data mining and Journal quality evaluation Find out who are audiences are Identify characteristics of high impact articles Measure effectiveness of innovations Outreach to related communities Special issues presenting high-impact work in designated subcommunities Addressing the needs of new research constituencies: engineers, biophysicists, clinicians Guidelines and templates for reviewers and associate editors: Shiva Das, Therapy Physics Editor We will discuss the Med. Phys. review process and a new initiative to create review templates that attempts to address current shortcomings. Template design is informed by the literature on of the review process effectiveness and practices of other journals. Its goals are to provide authors more constructive criticism to improve the manuscript; quantifying perceived importance and potential impact; and providing structured sections that prompt the reviewer to addresses important technical and editorial elements. While the template is recommended to be used, reviewers could alternatively enter their comments in the older free-form style. The expectations of the template are that it will enable consistently thorough, high quality reviews that accurately separate acceptable vs. substandard submissions but continue our tradition of helping authors to enhance papers with high potential. Ultimately, the goal is to reduce variability and subjectivity in the peer-review process, in turn leading to articles with higher research and clinical impact. We will also discuss interesting perspectives from several journals on aspects of the peer-review process such as public input via comments, influence of author-suggested reviewers, and bias in reviewer selection. Writing good scientific papers and responding to critiques: Mitch Goodsitt, Imaging Physics Editor The essential components of the abstract, introduction, methods, discussion and conclusion sections, as well as the desired writing style and style of the figures and tables will be reviewed. Publishable Medical Physics Ms. must include a clear and concise statement of the novelty and clinical and/or scientific importance of their work. Examples of novelty include: new technical solution to an important clinical problem; new generalizable knowledge; or first demonstration that an existing engineering solution solves a clinical problem. Authors must also include: sufficient background information and rationale; enough detail that the work can be reproduced by others; sufficient statistical analysis to refute or validate their hypothesis, how it compares to; is distinct from, and improves upon others' work; and the limitations of their study. When the authors receive critiques from the referees and associate editor, the authors should provide a detailed point-bypoint response to each comment. We now ask that the authors' rebuttal include the text of the original criticism, the authors' response, and the modified text along with the line numbers in the revised article. We also ask that the new text be highlighted in a different font color in the revised submission. These changes and others will be discussed. Their purpose is to facilitate the review process.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗

Technical Note: Image filtering to make computer-aided detection robust to image reconstruction kernel choice in lung cancer CT screening

Purpose: In lung cancer computed tomography (CT) screening, the performance of a computer-aided detection (CAD) system depends on the selection of the image reconstruction kernel. To reduce this dependence on reconstruction kernels, the authors propose a novel application of an image filtering method previously proposed by their group. Methods: The proposed filtering process uses the ratio of modulation transfer functions (MTFs) of two reconstruction kernels as a filtering function in the spatial-frequency domain. This method is referred to as MTF{sub ratio} filtering. Test image data were obtained from CT screening scans of 67 subjects who each had one nodule. Images were reconstructed using two kernels: f{sub STD} (for standard lung imaging) and f{sub SHARP} (for sharp edge-enhancement lung imaging). The MTF{sub ratio} filtering was implemented using the MTFs measured for those kernels and was applied to the reconstructed f{sub SHARP} images to obtain images that were similar to the f{sub STD} images. A mean filter and a median filter were applied (separately) for comparison. All reconstructed and filtered images were processed using their prototype CAD system. Results: The MTF{sub ratio} filtered images showed excellent agreement with the f{sub STD} images. The standard deviation for the difference between these images was very small, ∼6.0 Hounsfield units (HU). However, the mean and median filtered images showed larger differences of ∼48.1 and ∼57.9 HU from the f{sub STD} images, respectively. The free-response receiver operating characteristic (FROC) curve for the f{sub SHARP} images indicated poorer performance compared with the FROC curve for the f{sub STD} images. The FROC curve for the MTF{sub ratio} filtered images was equivalent to the curve for the f{sub STD} images. However, this similarity was not achieved by using the mean filter or median filter. Conclusions: The accuracy of MTF{sub ratio} image filtering was verified and the method was demonstrated to be effective for reducing the kernel dependence of CAD performance.

60 APPLIED LIFE SCIENCES↗

General Interaction Data Interface

The General Interaction Data Interface (GIDI) is a C++ API that reads and writes nuclear reaction data stored in the General Nuclear Data Structure (GNDS). GNDS is a new "format" for storing nuclear reaction data developed by the Working Party on Evaluation Co-operation (OECD/NEA/WPEC) Subgroup 38. GNDS can store evaluated nuclear data as well as nuclear data processed for deterministic (multi-group) and Monte Carlo transport. GIDI handles and provides accesses to all forms of the GNDS nuclear data. For multi-group data, GIDI provides functions to sum the data over all reactions. It also has functions for collapsing multi-group data to a small subset of groups and can transport correct multi-group data using the Pendlebury/Underhill formalism. The GNDS definition supports data for a PROjectile hitting a TARget for a given Evaluation. In GIDI this is called a PROTARE. For example, a neutron hitting O-16 from the ENDF/B-VIII.0 evaluation. To support a collection of protares, GIDI adds a Map class. The map class reads in a "map" file which specifies a list of projectile/target/evalaution's and their associated protare files. With a map instance, a user can request a specific projectile/target/evaluation and the map instance will return the requested protare.

Beck, Bret↗

Accelerating the Delivery of Home Performance Upgrades through a Synergistic Business Model

Achieving Building America energy savings goals (40% by 2030) will require many existing homes to install energy upgrades. Engaging large numbers of homeowners in building science-guided upgrades during a single remodeling event has been difficult for a number of reasons. Performance upgrades in existing homes tend to occur over multiple years and usually result from component failures (furnace failure) and weather damage (ice dams, roofing, siding). This research attempted to: A) understand the homeowner's motivations regarding investing in building science based performance upgrades; B) determining a rapidly scalable approach to engage large numbers of homeowners directly through existing customer networks; and C) access a business model that will manage all aspects of the contractor-homeowner-performance professional interface to ensure good upgrade decisions over time. The solution results from a synergistic approach utilizing networks of suppliers merging with networks of homeowner customers. Companies in the $\$ $400 to $\$ $800 billion home services industry have proven direct marketing and sales proficiencies that have led to the development of vast customer networks. Companies such as pest control, lawn care, and security have nurtured these networks by successfully addressing the ongoing needs of homes. This long-term access to customers and trust established with consistent delivery has also provided opportunities for home service providers to grow by successfully introducing new products and services like attic insulation and air sealing. The most important component for success is a business model that will facilitate and manage the process. The team analyzes a group that developed a working model.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Guide to Developing Energy Services Interfaces

This document provides guidance to develop communications interfaces that are highly interoperable and adhere to a set of energy services interface (ESI) principles. It can be applied in the context of information and communications technology interface standards and implementation profiles that enable the integration of a facility with responsive distributed energy resources (DER) into an electric power system consistent with the fundamental ESI principles. In this context, a DER facility may consist of a single DER with a communicating controller or may be as complex as a microgrid campus with several buildings and many DERs. This document is not a technical interface standard, but the requirements described can be used to check that existing, augmented, or new interface standards meet the interoperability requirements of the ESI concept. In this way, this guide for the ESI specification can support future advancements in developing interoperability standards and implementation profiles. The intended audience for this document is DER integration practitioners and ecosystem groups that are in the business of developing and implementing communications interfaces for DER integration. It is intended that these groups apply the information and processes in this document to develop communications standards and implementation profiles that are consistent with fundamental ESI principles.

2030.5↗

Evaluation of commercially-available spacecraft-type heat pipes

As part of an effort to develop reliable, cost effective spacecraft thermal control heat pipes, Lewis Research Center of NASA is conducting life tests on 30 commercially-available heat pipes in 10 groups of different design and material combinations. Materials are aluminum and stainless steel, and working fluids are methanol and ammonia. The formation of noncondensible gas is observed for times exceeding 11,000 hours. The heat transport capacities of the pipes are also determined. Considerable gas is found in two groups of methanol pipes; one group shows no gas. One group of ammonia pipes has no observable gas. Another group has much gas. Manufacturers' processing schedules are examined for differences explaining the presence of gas. Heat transport capacity is found to be severely reduced in some pipes containing gas.

Kaufman, W. B.↗

Spectral evolution of multiply-impulsive solar bursts

Hard X-ray and microwave observations of multiply-impulsive solar bursts, identified in the OSO-5 data were analyzed. Spectra in both frequency ranges were used to determine whether or not the source properties change from peak to peak within individual bursts. Two categories of microwave spectral behavior were identified: those events during which the microwave turnover frequency and spectral shape remain the same from peak to peak, and those during which the turnover frequency and spectral shape change significantly. These categories correspond to two classes of multiply-impulsive bursts: those for which the emission can be characterized by a constant magnetic field and therefore a single source region, in which case the multiplicity may be due to modulation of the emission process; and those in which groups of component spikes appear to originate in regions of different magnetic-field strengths, corresponding to separate source regions which flare sequentially. Examples of the latter type of events are presented. The discrete flaring regions are analyzed and their spatial separations estimated.

Karpen, J. T.↗

Transistor step stress program for JANTX2N2945A

Data compiled for the purpose of evaluating the effect of power/temperature step stress when applied to the transistor JANTX2N2945A manufactured by Raytheon and Teledyne is presented. A total of 48 samples from each manufacturer was divided equally (16 per group) into three groups and submitted to the processes outlined. In addition, two control units were maintained for verification of the electrical parametric testing.

Source record↗

Transistor step stress testing program for JANTX2N2484

The effect of power/temperature step stress when applied to the transistor JANTX2N2484, manufactured by Raytheon and Teledyne was evaluated. Forty-eight samples from each manufacturer were divided equally (16 per group) into three groups and submitted to the processes outlined. In addition, two control sample units were maintained for verification of the electrical parametric testing.

Source record↗

Materials processing in space programs tasks

Active research tasks as of the end of fiscal year 1981 of the materials processing in space program, NASA Office of Space and Terrestrial Applications are summarized to provide an overview of the program scope for managers and scientists in industry, university, and government communities. The program, its history, strategy, and overall goal are described the organizational structures and people involved are identified and a list of recent publications is given for each research task. Four categories: Crystal Growth; Solidification of Metals, Alloys, and Composites; Fluids, Transports, and Chemical Processes, and Ultrahigh Vacuum and Containerless Processing Technologies are used to group the tasks. Some tasks are placed in more than one category to insure complete coverage of each category.

Pentecost, E.↗

To Produce Nutrients for Plant Growth

On July 1, 1979 a new research program entitled "Development of a Prototype Experiment for Treating CELSS and PCELSS Wastes to Produce Nutrients for Plant Growth" was undertaken by the Massachusetts Institute of Technology and the Georgia Institute of Technology under grant from the National Aeronautics and Space Administration's Ames Research Center. The program was designed to be completed over a five-year period, with the work divided into two phases. Phase I covers approximately two years and involves the development of necessary facilities, chemical methodologies and models to allow meaningful experiments during Phase II, which will involve interfacing waste oxidation with plant growth. Homogeneous samples of freeze-dried human feces and urine have been prepared to assure comparability of results among various CELSS waste treatment research groups. A model of food processing wastes within a PCELSS was developed, and an initial batch of waste was prepared. An automated gas chromatographic system to analyze oxidizer effluents was designed and is operational. A state-of-the-art quantitative elemental analysis capability, built around inductively coupled plasma emission spectroscopy and atomic absorption spectroscopy using electrothermal atomization, has been demonstrated. A continuous flow wet oxidation system was constructed and is now operational.

Michael Modell↗

USSR Space Life Sciences Digest, issue 1

The first issue of the bimonthly digest of USSR Space Life Sciences is presented. Abstracts are included for 49 Soviet periodical articles in 19 areas of aerospace medicine and space biology, published in Russian during the first quarter of 1985. Translated introductions and table of contents for nine Russian books on topics related to NASA's life science concerns are presented. Areas covered include: botany, cardiovascular and respiratory systems, cybernetics and biomedical data processing, endocrinology, gastrointestinal system, genetics, group dynamics, habitability and environmental effects, health and medicine, hematology, immunology, life support systems, man machine systems, metabolism, musculoskeletal system, neurophysiology, perception, personnel selection, psychology, radiobiology, reproductive system, and space biology. This issue concentrates on aerospace medicine and space biology.

Hooke, L. R.↗

Human performance in aerospace environments: The search for psychological determinants

A program of research into the psychological determinants of individual and crew performance in aerospace environments is described. Constellations of personality factors influencing behavior in demanding environments are discussed. Relationships between attitudes and performance and attitudes and personality are also reported. The efficacy of training in interpersonal relations as a means of changing attitudes and behavior is explored along with the influence of personality on attitude change processes. Finally, approaches to measuring group behavior in aerospace settings are described.

Helmreich, Robert L.↗

Polyamideimides Containing Carbonyl And Ether Linkages

Polyamideimides of new class contain carbonyl and ether connecting groups. New polyamideimides more easily processable, stronger in tension, and more resistant to solvents (including water) than conventional polyamideimides. Improvements in mechanical and chemical properties attributable to semicrystallinity introduced into otherwise amorphous polymers by incorporation of carbonyl and ether linkages.

Hergenrother, Paul M.↗

Product traceability for NASA space systems

Identification as a specific point in a quality publication revealed in the year 1962, that it was a somewhat controversial subject with something lacking in groundrule definitions. The basic key to 'traceability' is establishment of proper identification numbers. These are: (1) serial numbers for control of individual articles, assemblies or equipment; (2) lot numbers for control of materials, articles and/or assemblies produced in homogeneous groups or through a controlled process; (3) date codes on articles or materials made by a continuous or controlled process and on such items subject to variations or degradation with age; or (4) combinations of the above.

Dyer, Morris K.↗

Recommendations for future research in hypersonic instrumentation

An overview of the NATO Advanced Research Workshop is presented. It describes the process followed to obtain a group consensus on the main technical recommendations for each of the five technical sessions of the Workshop and presents the general conclusions and recommendations for future research agreed upon by the workshop participants.

Ocheltree, S. L.↗

Basalt generation at the Apollo 12 site. Part 2: Source heterogeneity, multiple melts, and crustal contamination

The petrogenesis of Apollo 12 mare basalts has been examined with emphasis on trace-element ratios and abundances. Vitrophyric basalts were used as parental compositions for the modeling, and proportions of fractionating phases were determined using the MAGFOX prograqm of Longhi (1991). Crystal fractionation processes within crustal and sub-crustal magma chambers are evaluated as a function of pressure. Knowledge of the fractionating phases allows trace-element variations to be considered as either source related or as a product of post-magma-generation processes. For the ilmenite and olivine basalts, trace-element variations are inherited from the source, but the pigeonite basalt data have been interpreted with open-system evolution processes through crustal assimilation. Three groups of basalts have been examined: (1) Pigeonite basalts-produced by the assimilation of lunar crustal material by a parental melt (up to 3% assimilation and 10% crystal fractionation, with an 'r' value of 0.3). (2) Ilmenite basalts-produced by variable degrees of partial melting (4-8%) of a source of olivine, pigeonite, augite, and plagioclase, brought together by overturn of the Lunar Magma Ocean (LMO) cumulate pile. After generation, which did not exhaust any of the minerals in the source, these melts experienced closed-system crystal fractionation/accumulation. (3) Olivine basalts-produced by variable degrees of partial melting (5-10%) of a source of olivine, pigeonite, and augite. After generation, again without exhausting any of the minerals in the source, these melts evolved through crystal accumulation. The evolved liquid counterparts of these cumulates have not been sampled. The source compositions for the ilmenite and olivine basalts were calculated by assuming that the vitrophyric compositions were primary and the magmas were produced by non-modal batch melting. Although the magnitude is unclear, evaluation of these source regions indicates that both be composed of early- and late-stage Lunar Magma Ocean (LMO) cumulates, requiring an overturn of the cumulate pile.

Neal, Clive R.↗